RESUMEN
Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) in young adults that has serious negative socioeconomic effects. In addition to symptoms caused by CNS pathology, the majority of MS patients frequently exhibit gastrointestinal dysfunction, which was previously either explained by the presence of spinal cord lesions or not directly linked to the autoimmune etiology of the disease. Here, we studied the enteric nervous system (ENS) in a B cell- and antibody-dependent mouse model of MS by immunohistochemistry and electron microscopy at different stages of the disease. ENS degeneration was evident prior to the development of CNS lesions and the onset of neurological deficits in mice. The pathology was antibody mediated and caused a significant decrease in gastrointestinal motility, which was associated with ENS gliosis and neuronal loss. We identified autoantibodies against four potential target antigens derived from enteric glia and/or neurons by immunoprecipitation and mass spectrometry. Antibodies against three of the target antigens were also present in the plasma of MS patients as confirmed by ELISA. The analysis of human colon resectates provided evidence of gliosis and ENS degeneration in MS patients compared to non-MS controls. For the first time, this study establishes a pathomechanistic link between the well-established autoimmune attack on the CNS and ENS pathology in MS, which might provide a paradigm shift in our current understanding of the immunopathogenesis of the disease with broad diagnostic and therapeutic implications.
Asunto(s)
Autoanticuerpos/sangre , Enfermedades Gastrointestinales/etiología , Esclerosis Múltiple , Animales , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/patología , Citocinas/metabolismo , Modelos Animales de Enfermedad , Sistema Nervioso Entérico/metabolismo , Sistema Nervioso Entérico/patología , Sistema Nervioso Entérico/ultraestructura , Femenino , Adyuvante de Freund/toxicidad , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/inmunología , Esclerosis Múltiple/patología , Músculo Liso/patología , Músculo Liso/ultraestructura , Proteína Básica de Mielina/inmunología , Proteína Básica de Mielina/metabolismo , Proteína Básica de Mielina/toxicidad , Glicoproteína Mielina-Oligodendrócito/inmunología , Glicoproteína Mielina-Oligodendrócito/toxicidad , Plexo Mientérico/patología , Plexo Mientérico/ultraestructura , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/toxicidad , Tubulina (Proteína)/metabolismoRESUMEN
BACKGROUND: There are a number of instruments that describe severity and progression of multiple sclerosis and they are increasingly used as endpoints to assess the effectiveness of therapeutic interventions. We examined to what extent the psychometric properties of two accepted instruments--EDSS and MSFC--meet methodological standards and the value they have in clinical trials. METHODS: We conducted a systematic literature search in relevant databases [MEDLINE (PubMed), ISI Web of Science, EMBASE, PsycINFO & PSYNDEX, CINAHL] yielding 3,860 results. Relevant full-text publications were identified using abstract and then full-text reviews, and the literature was reviewed. RESULTS: For evaluation of psychometric properties (validity, reliability, sensitivity of change) of EDSS and MSFC, 120 relevant full-text publications were identified, 54 of them assessed the EDSS, 26 the MSFC and 40 included both instruments. The EDSS has some documented weaknesses in reliability and sensitivity to change. The main limitations of the MSFC are learning effects and the z-scores method used to calculate the total score. However, the methodological criterion of validity applies sufficiently for both instruments.For use in clinical studies, we found the EDSS to be preferred as a primary and secondary outcome measure in recent studies (50 EDSS, 9 MSFC). CONCLUSIONS: Recognizing their strengths and weaknesses, both EDSS and MSFC are suitable to detect the effectiveness of clinical interventions and to monitor disease progression. Almost all publications identify the EDSS as the most widely used tool to measure disease outcomes in clinical trials. Despite some limitations, both instruments are accepted as endpoints and neither are discussed as surrogate parameters in identified publications. A great advantage of the EDSS is its international acceptance (e.g. by EMA) as a primary endpoint in clinical trials and its broad use in trials, enabling cross-study comparisons.